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Aufsatz
Mapping the field of research on African higher education: a review of 6483 publications from 1980 to 2019
(2020-11-16)
Following a global trend, higher education (HE) in Africa has also become a complex enterprise, potentially demanding specific expertise in higher education research. However, despite this, there is a dearth of analysis into the state of research on African HE. This paper seeks to fill this gap by mapping and analysing African HE research. We undertake a systematic review of 6483 articles and books focusing on African HE published from 1980 to 2019 in indexed and non-indexed journals and book-publishers. We particularly ...
Aufsatz
Strategic framing of genome editing in agriculture: an analysis of the debate in Germany in the run-up to the European Court of Justice ruling
(2021-10-09)
New techniques in genome editing have led to a controversial debate about the opportunities and uncertainties they present for agricultural food production and consumption. In July 2018, the Court of Justice of the European Union defined genome editing as a new process of mutagenesis, which implies that the resulting organisms count as genetically modified and are subject, in principle, to the obligations of EU Directive 2001/18/EG. This paper examines how key protagonists from academia, politics, and the economy ...
Aufsatz
Das Potenzial kooperativen Lernens ausschöpfen: Die Bedeutung der transaktiven Kommunikation für eine lernwirksame Zusammenarbeit
(2021-10-26)
Kooperatives Lernen eröffnet Chancen und birgt gleichzeitig Risiken für den Wissenserwerb. Der Beitrag arbeitet die Bedeutung der transaktiven Kommunikation als zentralen Wirkmechanismus für den genuinen Mehrwert kooperativen Lernens heraus. Unter transaktiver Kommunikation wird die fachinhaltliche Bezugnahme auf den Lernpartner verstanden, wobei niedrig-transaktive (z.B. paraphrasierende) von hoch-transaktiven (z.B. integrierenden) Äußerungen unterschieden werden. Es werden Bedingungen, unter denen sich transaktive ...
Aufsatz
The financialization of remittances and the individualization of development: A new power geometry of global development
(2021-08-23)
The article argues that the increasing financialization of remittances produces an enormous shift in the political economy of development and contributes to a new power geometry of development. Exploring this power geometry, the article focuses on three main issues: First, migrants intend to support their friends and families on an individual level as remittance senders, and together with the corresponding recipients they form a translocal moral economy. On a macro level, the value of these transactions is high when ...
Aufsatz
High optical gain in InP-based quantum-dot material monolithically grown on silicon emitting at telecom wavelengths
(2022-04-01)
We describe the fabrication process and properties of an InP based quantum dot (QD) laser structure grown on a 5° off-cut silicon substrate. Several layers of QD-based dislocation filters embedded in GaAs and InP were used to minimize the defect density in the QD active region which comprised eight emitting dot layers. The structure was analyzed using high resolution transmission electron microscopy, atomic force microscopy and photoluminescence. The epitaxial stack was used to fabricate optical amplifiers which ...
Aufsatz
Adsorption of PCE in alkali-activated materials analysed by fluorescence microscopy
(2021-10-18)
The realisation of high-performance concrete mixtures requires the use of superplasticizers to achieve a low water/binder ratio and thus high strengths. Polycarboxylate ethers (PCE) are mostly used as superplasticizers. The effectiveness of these superplasticizers depends on their chemical structure, the binders’ alkaline environment and the ions present in the pore solution of the binder. In high alkaline systems like some alkali-activated materials no effective superplasticizer have been found yet. To unravel the ...
Aufsatz
Development and Experimental Study of Smart Solar Assisted Yogurt Processing Unit for Decentralized Dairy Value Chain
(2022-04-04)
Yogurt production at the farm level is important for adding value to milk. In this study, a solar-assisted yogurt processing unit capable of performing the three processes of heating, fermentation, and cooling in a single unit was developed. It consisted of a circular chamber surrounded by a coil for heating by a solar vacuum tube collector and a pillow plate for cooling by a solar PV-powered chiller unit. Experiments were performed using 50, 40 and 30 L of raw milk under a constant water circulation rate of 50 L per ...
Aufsatz
Simulation framework for crystallization in melt flows of semi-crystalline polymers based on phenomenological models
(2022-04-16)
Polymer components are shaped mostly out of the molten state. As in the case of semi-crystalline polymers, crystallization can be suppressed by shock cooling, thermal process design allows to influence the solid bodies properties. A simulation approach that enables to predict these properties based on a forecast of crystallinity is presented in this paper. The main effects to consider and possibilities of modeling and simulation are discussed. A detailed description of how to create an experimental foundation using ...
Aufsatz
Environmental Assessment of Carbon Concrete Based on Life-Cycle Wide Climate, Material, Energy and Water Footprints
(2022-07-12)
The construction industry contributes a major share to global warming and resource consumption. Steel-reinforced concrete (SC) is the world’s most important building material, with over 100 million cubic meters used per year in Germany. In order to achieve a resource-efficient and climate-friendly construction sector, innovative technologies and the substitution of materials are required. Carbon concrete (CC) is a composite material made of concrete and a reinforcement of carbon fibers. Due to the non-rusting and ...
Aufsatz
Physicochemical Investigation of Rainfall for Managed Aquifer Recharge in Punjab (Pakistan)
(2022-07-07)
In a water-scarce country such as Pakistan, rainfall is the third-largest source of freshwater. In most of the urban cities of the country, rainwater is mixed with sewerage and is rendered useless for managed aquifer recharge purposes. Therefore, this study investigates the rainfall potential for managed aquifer recharge in Lahore (Pakistan). The present research was designed and conducted by the Irrigation Research Institute (IRI). Three different sites were selected for rainwater sample collection across the study ...